JP2002-92678A (WO02/23493, U.S. Pat. No. 6,783,452) describes a coin sorting system including a presorting device that presorts coins into three groups as a disc rotates. The coin sorting system additionally includes two rectilinear main sorting devices that further sort by respective denominations two of the three coin groups presorted by the presorting device. These main sorting devices each have four sorting structures (sorting holes) each configured to eject coins of a particular denomination. The coins that have been ejected by the respective sorting structures are collected into corresponding coin receiving units (temporary storage) through chutes.
Incidentally, the number of coin denominations varies from currency to currency. For example, the Euro circulates in eight denominations, and US dollars in five denominations (except for rare one-dollar coins). In general, the sizes and circulation volumes of coins also vary according to denominations.
Accordingly, the number of coin receiving units (e.g., eight) is set with one of the currencies largest in the number of denominations (e.g., the Euro) as a reference. If a currency whose number of denominations is smaller than eight (e.g., US dollar) is to be handled, two coin receiving units are assigned to each of at least one sorting structure (e.g., three sorting structures). In this case, two chutes along which the coins ejected from the sorting structure will be guided into the two receiving units are provided to allow coin route switching to either of the two chutes. When the number of coins of a particular denomination (e.g., US 25-cent) that have been collected into one of the two receiving units reaches a previously set number N, the chute (the route of the coins) is switched so that further coins will be collected into the other receiving unit.
In this case, denominations of the coins are discriminated by using a discrimination sensor provided at the coin-introducing side of the sorting device. The last coin to be collected from the sorting structure into one receiving unit (i.e., the N-th coin) and the first coin to be collected into the other receiving unit (i.e., the (N+1)-th coin) are identified on the basis of the discrimination results. It is practically impossible, however, to switch the chute timely between the last coin and the first coin while sorting the coins at high speed. In order to compensate for this inconvenience, therefore, the introduction of coins is temporarily stopped immediately after the last coin has moved past the discrimination sensor, and then the chute is switched before the introduction of the remaining coins is restarted.